1. Field of the Invention
The present invention relates to a device for driving a stepping motor.
2. Description of the Prior Art
An exposure apparatus has heretofore been known which includes an exposure head having light-emitting elements and a rotating drum having a cylindrical surface disposed opposite the exposure head, and which horizontally scans a photosensitive material wound around the rotating drum by rotating the rotating drum around the shaft thereof and vertically scans it by moving the exposure head in the axial direction of the rotating drum so as to expose the exposure surface of the photosensitive material. Such an exposure apparatus employs a stepping motor for moving the exposure head along the axis of the rotating drum. The stepping motor is driven during the vertical scanning of the exposure by a drive signal which is either a video signal or a digital signal. When the exposure is conducted with a video signal, it is necessary for the stepping motor to be driven continuously. With the latter, the stepping motor is required to be driven intermittently. Conventionally, the stepping motor is therefore driven by two separate drive devices: one which is employed when the exposure is conducted with the video signal and the other being employed with the digital signal.
As two types of devices for driving the stepping motor are necessary in the known exposure apparatus in correspondence with the signal employed, the exposure apparatus must be equipped with devices of two types if the photosensitive material is exposed with either video or digital signals. Further, both the drive device specifically used for digital signals and the drive device for video signals must be manufactured, and the total number of parts required for the two drive devices is therefore raised, increasing the production cost.